OEMs respond to federal mandates
Given the possible complications of roadside breakdowns, inclement weather, driver fatigue, and other factors that can impair driver vision, vehicle visibility is a primary safety concern.
Studies have demonstrated that reflective markings can significantly reduce fatal accidents involving automobile drivers who crash into the backs of vehicles and under-ride them. Consequently, regulations mandating their use on new trailers and tractors are now in effect. (The Maintenance Council of ATA has issued Recommended Practice 722, which establishes minimum design, configuration, and dimensional criteria for such reflective marking systems. For information, call ATA at 703-838-1845.) Moves are also under way to mandate their use on older vehicles, which means that widespread retrofitting could be in the offing.
Manufacturers of reflective products are moving toward the development of new materials that will increase the power and stackability of photometric sheeting. This sheeting has been used on traffic signs since the early 1950s, when 3M pioneered a durable enclosed lens that is still used in slow-speed, low-density traffic areas.
The original 3M lens, dubbed "Engineer Grade," has since been upgraded. High Intensity Grade is three times brighter and guaranteed to retain at least 80% of its original illumination after 10 years on the road.
Both Engineer and High Intensity grades use many tiny glass beads behind a durable transparent plastic shield, backed by a reflector coat and a protective liner. The Engineer uses an enclosed lens, while High Intensity features an encapsulated lens.
In both cases, incoming (incident) light bends (refracts) as it passes through the front surface of each spherical glass bead and reflects off a mirrored surface behind. The beam then passes through the front surface, is refracted as it leaves the bead, and returns towards the light source.
3M's top-of-the-line product, Diamond Grade, is a cube corner reflective sheeting that is at least three times brighter than encapsulated lens sheeting and up to ten times brighter than enclosed sheeting. Like beads, cube corners are retroreflective lens elements that deal with incoming light in much the same the way that the corner of a room bounces a ball that is thrown into it, giving a sharper reaction than a spherical shape.
Diamond Grade performs at entrance angles up to 60 deg. (These are the angles referred to when discussing the "angularity" of reflective sheeting.) This angle is especially important when vehicles are stopped far off the shoulder, on the left-hand side of the road, on curves, or in bad weather, because the incident light is not coming head-on.
Reflexite North America has launched a new conspicuity product designed for Europe's curtainside trailer market, but which is now available in the U.S. Although European standards for reflective markers are different than U.S. standards, Reflexite says the European standards exceed U.S. requirements.
The product is available with two substrates -- rigid steel and fiberglass, the latter of which is particularly suited for flexible application.
Stimsonite's Series 4560 vehicle conspicuity tapes exceed NHTSA requirements 49 CFR 571; each strip carries the DOT-C legal certification for compliance. The tape outlines the vehicle with a continuous line of alternating red and white segments, providing it with extremely visible, high-contrast markings.
According to Stimsonite, the tape's bright red color is protected by a UV-absorbing film, which also resists the effects of weather, dirt, and time.
The tape uses a modular pattern of reflective prisms that can be mounted in any position without diluting its effectiveness. Constructed of tough, clear 100% polymethylmethacrylates, chosen for their exterior durability, the tape is backed by a seven-year limited warranty.
Series 4560 tape is available in 2-in., 50-yd. rolls (11 in. red/7 in. white); 6-in. squares; and 2-in., 50-yd. rolls of white only. Series 6200, which was developed for school bus use, is said to be highly resistant to vandalism.
Betts Spring Co. recently introduced two reflector strips that meet DOT conspicuity requirements. The RT25 fits all straight standard, heavy-duty, and spring-loaded mud flap hangers, as well as the rear flap brackets of most trailers. A standardized pattern makes it appropriate for either the right or left side of the vehicle.
Multiple mounting holes on the RT35 angled reflector strip ensure that this product can be applied to virtually all flap hangers. The pattern has been designed to provide a symmetrical look to the rear of the tractor.
Both RT25 and RT35 reflector tape can be easily installed between the mud flap and the flap hanger, which means it can be used on trucks that are already in service. The edges of the tape are sealed for added durability and corrosion resistance.